Electrical therapeutic stimulators are well known. For the treatment of pain, there are devices such as a transdermal electrical nerve stimulator (TENS) unit or interferential stimulators that use an interferential stimulation set up by the beating of pulses applied at two different frequencies. For muscle stimulation for rehabilitation or training, there are devices that use biphasic square wave pulses, a pulsed direct current stimulation or galvanic current stimulation. These devices can also be used for pain management and edema reduction. Originally, electrical therapeutic stimulators were tabletop sized devices. More recently, smaller handheld devices have been developed. Today, some devices are small enough to be applied like a bandage to a desired area of the body to be stimulated. Devices have also been designed to deliver treatment modalities with different waveforms packaged into a single device.
It is common practice for therapists, physicians, athletes, and other individuals to utilize various treatment modalities and electrical therapy devices to promote muscle training, conditioning, and rehabilitation. With muscle stimulation and nerve stimulation, a device is programmed to output various levels of electrical pulses. The waveforms, frequency, duration, pulse width, intensity, and output modalities of the output signal control the directed treatment goals.
With regard to muscle stimulation, there are a myriad of uses for these electro-stimulation devices. Treatment categories can generally be divided between muscle fitness, muscle aesthetic, sport training, muscle rehabilitation, and vascular therapy. Each category is directed to a different stimulation goal. With muscle fitness, the goal is generally to restore, improve, or maintain a good physical condition by building muscle, muscle tone, volume, trophism, metabolism, and the like. With muscle aesthetic goals, a stimulator is often utilized on muscles in order to shape, firm, refine, increase elasticity, and increase caloric expenditure. Sports-minded individuals may use a device to increase muscular endurance and strength, increase blood flow to promote active recovery, and the like. When focus is on muscle rehabilitation, muscular stimulation is needed to restore or otherwise redevelop a convalescent muscle. Under the vascular category of treatment programs, the goal is to improve blood circulation in the stimulated area to promote healing and minimize circulatory problems, fatigue, lack of oxygenation, swelling, and other related problems.
Regardless of the unique goal-dependent outputs of the device, electro-stimulation for muscle stimulation works under a principle of voluntary muscle contraction. When individuals contract a muscle, the brain sends the information to the muscle via the motor nerve. With electro-stimulation, a suitable electric current acts directly on the nerve by means of electrical impulses that reproduce the natural physiological phenomenon. These electrical impulses are applied to the user through attached electrodes. The electrodes are typically adhesively attached to the person or person's clothing. With electro-stimulation a patient or user can achieve intensive muscular work without mental or cardiac fatigue, thus reducing joint and tendon constraints. U.S. Pat. No. 6,324,432, commonly assigned with the present application to Compex SA, discloses an electrical neuromuscular stimulator for measuring muscle responses to electrical stimulation pulses, and U.S. patent application Publication No. 2003/0074037 discloses an electrical nerve stimulation device. U.S. Pat. No. 6,324,432 and U.S. patent application Publication No. 2003/0074037 are incorporated herein by reference in their entireties.
However, conventional electro-stimulation devices, while useful in achieving intensive muscular work for a target or generalized muscle set, are not capable of self-adjusting for various muscle groups. Conventional devices are also not capable of automatically adjusting for various users; even though two patients may be seeking the same general therapeutic or training effects, each may be at a different fitness or recovery stage. Further, conventional electro-stimulation devices are not generally able to self-adjust for detected physiological traits of a particular user.
In pain management applications, electro-stimulation devices are used primarily to alleviate pain and discomfort, including chronic intractable pain, post surgical pain, and post traumatic pain, and to increase blood flow. Increasing blood flow, for example, fosters healing. TENS, microcurrent, and interferential electrotherapy stimulation techniques have been used successfully for the symptomatic relief and management of chronic intractable pain for many years. In general, TENS or micro current electrical nerve stimulation controls pain of peripheral origin by providing a counter stimulation that interferes with the painful sensations.
In one application according to gate control theory, small electrical impulses are sent through the skin into a painful area. These electrical impulses are harmless but reach the nerves and cause a mild tingling sensation. Gate control theory states that as pain impulses travel through a nerve to the spinal cord and brain, the pain impulses can be altered or modified at certain points along the route. Pain signals are carried to the brain via small diameter, slow conducting nerve fibers. This transmission can be blocked by stimulating larger diameter, fast conducting nerve fibers. The signals along the fast conducting nerve fibers normally reach the brain before those traveling along the slow conducting nerve fibers. If the larger fibers are stimulated without much activity of the smaller pain fibers, the “gate” is closed and pain is lessened and/or blocked.
Interferential (IF) stimulation is used for symptomatic relief and management of chronic intractable pain and for increasing blood flow. IF stimulation is also used as an adjunctive treatment in management of post surgical and post traumatic pain. In this therapeutic treatment, two or more electrical signals having varying frequencies and/or phases are induced in a patient's tissue, where the signals combine, or interfere, to form a modulated signal that is effective for pain treatment and management.
Conventional stimulation devices, however, frequently require application and supervision by a trained medical professional to prevent muscle over-stimulation, fatigue, or, in extreme situations, injury. As these electronic devices have improved and been reduced in size, there has been a trend toward providing ever-increasing flexibility and greater programming options for such devices. U.S. Pat. No. 6,674,048 is one example of such a handheld electro-medical device. The handheld device features a single LCD touch-sensitive screen on which a wide variety of programming control and directions are provided to both the clinician and the user.
The need remains, however, for an electrical muscle stimulation device and corresponding electrode system that substantially addresses the innate drawbacks of conventional devices and systems. For example, while the enhanced functionality and features of handheld electrical therapeutic stimulators offer more treatment options, the complexity of these devices can offset the effectiveness of this enhanced functionality, particularly in older patient populations. Accordingly, it would be desirable to provide for a handheld electrical therapeutic stimulator that is simpler and easier to use while providing expanded functionality.